Apparatus for refining paper stock



Feb. 2o, 1934. J, A, DE GEW 1,947,900

APPARATUS FOR REFINING PAPER STOCK Filed June 25, 1931 ffiiiiiifiiiiiifiiiiiiffii Patented Feb. 20, 1934 UNITED STATES PATENTOFFICE The jordan is a machine that is used in paper mills for refiningpaper stock after .the ingredients have been blended together inbeaters, the jordaning operation being the last operation in preparingthe stock for the paper machine.

These machinesconsist of a moving part in the form of a' cone whichrevolves inside of a stationary surface, both surfaces being lined witha series of knives or filling resembling knives. As these machines aregenerally operated in such a manner that the revolving portion acts as apump by throwing the stock from a smaller circumference to a larger one,the revolving portion of the machine is the transporting force of thestock through the machine.

These machines are always constructed so that the knives of bothsurfaces are exposed and between these knives there are spaces calledtransporting notches, in which the stock can be held. In an ordinaryjordan the depth of the transporting notches between the knives is about#to 1/", and it is common practice to keep the depth of the transportingnotches constant by cutting out a portion of the wood between the kniveswhen the knives wear down. The depth of the notches between the knivesand the shell is equal to that in the plug or revolving surface, andinasmuch as the circumference of the shell is larger than the plug,there is really more area between the knives of the shell than betweenthe knives of the plug.

When these machines are operated at a very low head of stock above themachine then the plug transports practically all. of the stock and thatwhich lls the spaces between the knives of the shell is practicallystationary. If, however, the stock is forced through the jordan by someother impelling force than the pumping action of the revolving plug,such as for instance using a high static head or pump pressure at thejordan inlet or a vacuum at the outlet of the jordan,ythen there is atendency for the material to move through the jordan not only within thetransporting notches of the plug but also between the notches of theshell. That portion of stock which is therefore held in the shell by thepressure of centrifugal force will move along through the jordan withoutreceiving any treatment whatsoever from the knives of the plug.

If by the use of pressure at the inlet or of vacuum` at the outlet, astock of high density is used, then this stock will not only be heldmore rmly within the spaces in the shell but it will be held between thespaces in the plug as well, and be revolved in a spiral manner withoutleaving these transporting spaces and will not receive treatment by theshearing action of the revolving knife surfaces.

It is the purpose'of this invention to so construct and operate thejordan that all stock passing through it mst be treated by the knivesand in order to accomplish this, especially when pressure is used at theinlet of the jordan, it is necessary to so construct the fillings thatthe flow of' stock must all pass between and be discharged from theparallel knives or segments of the moving part, as for instance thejordan plug. This means a revision of the design of the shell of thejordan or the stationary part of any refining engineso that it exposesan abrasive surface but no material transporting spaces within thissurface. It also means new design of the jordan plug. In the case of anordinary jordan the spaces between the knives of the shell can beentirely filled with the pieces of wood that separate and hold theseknives or the knives in the shell can be worn down to the wooden llingand not chipped out as is done by the present practice. On the otherhand, the shell of the jordan or the stationary part of any rener can beconstructed of a material which offers an abrasivesurface such ascarborundum, basalt lava, porous iron or any ribbed or roughenedmaterial in which there are no spaces which could be called transportingnotches. By this method of refining the stock is B5 thrown in a. spiraldirection by the centrifugal force of the revolving means, against theuniformly rough surface and the bres not being able to escape intoopposing spaces is obliged to remain within the sphere of the refiningaction of the revolving surfaces.

I therefore prefer to construct the machine so that the stationaryportion is lined with an abrasive material whereas the revolving surfaceor the plug of the jordan may be constructed in the ordinary manner withsteel or bronze knives with transporting notches between them or it mayalso be constructed of segments of abrasive material with substantiallyparallel transporting notches between these segments. In any case, thematerial is retained between the spaces existing inthe revolving portionof the machine and moves in a direct manner along the plug and in aspiral direction with reference to the shell, and consequently it has anopportunity to be thrown out of any space in which it is contained andcaught in another one in the same plane of motion.

The jordan generally has both long and short knives, some going the fulllength of the plug and others only covering that portion of the plughaving the larger circumference. The volume of the spaces between theknives at the larger end of the plug is always much greater than at thesmall end so that when stock enters the jordan it may ll the spacesbetweenthe knives at the large end. I therefore arrange the spacing ofthe knives and the depth of the notches so that the transporting area atthe inlet is approximately equal or less than the transporting area atthe maximum diameter of the plug and the intermediate spacesso'proportioned that they have similar total area of transporting space.This means putting more knives than usual in the large portion of thejordan or else gradually reducing the depth of the notches as thediameter of the plug increases. In most cases it is desirable toactually reduce the transporting area at the large end of the plug toless than that at the small end.

This is a new principle in jordan design and although the result may beaccomplished in various ways, yet the essential part of the invention isthat'the stock passes through more restricted areas as its viscositygrows less and the velocity increases. The conical construction is moreoi less standard and is builtthus to assist in the transporting of thematerial by centrifugal force, but by my design and process of operationthis advantage can be retained without having the disadvantage ofpassing the stock through a small space and allowing this space toexpand so that the material is thrown apart and not kept in a solidmass.

The basis of this invention therefore, is that the stock in passingthrough the jordan is all transported in a spiral movement by the plugbut in its passage through the plug it is held within approximately aspace of constant volume or reduced volume` This method of operating arefiner is one that has been overlooked by the industry up to thepresent, as is shown by observation of the designs and construction ofexisting machines, especially jordans in which the construction of thelining of the shell is similar to that of the plug or revolving part. Iprefer to use a material for the shell consistlng of an abrasivematerial such as lava stone, carborundum, porous iron, etc., and for theplug parallel bars of iron, steel, bronze or abrasive material withtransporting notches between them of sufhcient area to carry the volumeof stock desired to be passed through the machine. These plugs are sodesigned that the depths of the notches grow less as the diameter of theplug increases. These metal bars may be tilted towards the direction ofow and the stone or abrasive bars are bevelled so that the transportingspaces have a wedge shape, with the apex of the wedge where the stockenters the grinding surface and the area of this wedge like space,becomes smaller as it approaches the discharge end of the machine.

For detailed description of the method of operation of this invention,reference is now made to the accompanying drawing.

Figure 1 is a semi-sectional isometric view showing one form of the plugof this invention in place in its shell. Figure 2 is a view similar toFigure l but of a different embodiment of the invention. Figure 3 is apartial end view of the plug element shown in Fig. 1 looking from thesmall end toward the larger end. Figure 4 is a view similar to Figure 3but showing the plug element of Figure 2. Figure 5 shows aconstructional detail.

In Figures 1 and 3 a rener or jordan shell 1 is shown with a taperedbore in which operatively rotates a truncated cone shaped plug element.The plug element is formed of a main body portion 3 made up for exampleof wooden spacers. The longitudinal or peripheral surface of the bodyportion is non-parallel to the bore of the shell 1. That is, theclearance between the periphery of the body 3 and the bore of the shellat the smaller end of the plug is greater than the clearance betweenthese elements at the larger end'. Another way of saying it is that thetaper on the body portion of the plug is greater than the taper of thebore in the shell.

On the body portion or wooden spacers 3 of the plug, longitudinallyextending steel bars or knives 2 extend radially from the body portion 3of the plug in a manner whereby the longitudinal edges of the knives 2are parallel to the bore of the shell 1. This arrangement creates a plugelement having knives extending therefrom which are parallel to theshell bore but a body portion which is non-parallel to the shell bore.Thus a depression 4 is formed between two adjacent knives which isdeeper at the smaller end of the plug and shallower at the larger end 5thereof. Stock to be rened flows through the depression 4 from thesmaller end of the plug to 5 in the larger end. These depressionstherefore gradually decrease in depth as the larger end of the plug isencountered. The number of knives progressively increase toward thelarger end of the plug, as shown in the drawing. To bring about acritical relationship of the depressions, grooves or spaces 4 betweenthe blades, the relationship is that the total area of the depressionsor grooves at the larger outlet end of the plug is less than the totalarea of the grooves or depressions at the smaller or inlet end of theplug. The purpose of this is to set up a certain amount of resistance tothe flow of stock through the rener. The reflner of the stock takesplace between the edges of the knives and the shell, which is preferablymade of some abrasive material, whereas the depressions or grooves 4transport the stock through the rener.

In Figures 2 and 4 the plug is made of segments 6, preferably ofabrasive material suitably held together to form a plug element whoseexterior periphery is tapered to be parallel to the taper of the shellboard. This truncated cone-shaped plug element is provided with stocktransporting grooves 7 extending the entire length of the plug but beingtapered at 8 at the smaller end of the plug and progressively becomingshallower to 9 at the larger end of the plug. These grooves ordepressions which decrease in depth as the larger end of the plug isreached, correspond and are equivalent to the depressions 4 which alsodiminish in depth as described for Figure 1. However, the grooves inthis embodiment are provided with a bevel or curve in the trailing edgeof the groove as shown in Figure 5 to facilitate escape of stocktherefrom in a direction opposite to the rotation of the plug as shownin that figure. Thus in both embodiments of this invention whereas thediameter of the plug increases, the total free area between the plug andthe shell at the larger end is less than the total free area between theplug and the shell at the smaller end.

It is understood that the present disclosure is for the purpose ofillustration only, and that the invention is not limited thereto. Tothose skilled in the art, many modifications of the invention will bereadily apparent, and it will also be obvious to such skilled personsthat part of the device may be used without other parts thereof, manysuch combinations of the parts readily suggesting themselves. Therefore,it should be, and is to be distinctly understood that for a denition ofthe limitations of the invention, reference must be had to the appendedclaims.

I claim:

1. In a pulp rener having a smaller inlet end and a larger outlet end, ashell provided with a tapered bore, a plug element rotatably mounted insaid bore having longitudinal portions parallel to said bore and otherlongitudinal portions nonparallel thereto whereby the area of the freespacev between the plug and shell at the larger outlet end is less thanthe area of the free space between the plug and shell at lthe smallerinlet end.

2. In a pulp renner, a shell having a tapered bore, a truncated coneshaped plug element rotatably mounted therein comprising a body portion,longitudinally extending knives projecting therefrom progressivelyincreasing in number toward the largerY end of the plugl characterizedby the fact that the total space between all the knives at the largerend of the plug is less than the similar space at the smaller endthereof.

3. In a pulp reflner, a shell having a tapered bore, a truncated coneshaped plug element rotatably mounted therein comprising a body portionextending from end to end thereof, and stock transporting groovesgradually decreasing in depth toward the larger end of said plug whosetrailing wall is sloped to facilitate escape of stock therefrom in adirection opposite to the rotation o1' the plug.

JU'DSON A. DE CEW.

